This application claims the benefit of German patent application 101 50 591.4, filed Oct. 12, 2001, herein incorporated by reference.
The present invention generally relates to a yarn splicing device.
Yarn splicing devices for the pneumatic connection of two yarn ends have been known for a long while in connection with automatic cheese winders.
Yarn splicing devices are known, wherein the yarn insertion slot of a splicing channel arranged in a so-called splicing head remains uncovered during the splicing process, as well as splicing devices wherein this yarn insertion slot is closed by a special cover element during the splicing process.
For example, German Patent Publication DE 39 35 536 C2 discloses a yarn splicing device having a splicing head whose splicing channel has an approximately circular cross section. Compressed air injection openings terminate tangentially in the splicing channel. Moreover, on its top the splicing channel has a continuous slot, through which the yarn ends to be spliced together can be threaded. This yarn insertion slot can be closed by means of a cover element during the splicing process.
Basically, such yarn splicing devices with or without cover elements have proven themselves in actual use.
However, difficulties in inserting the yarn end into the splicing channel occasionally arise in connection with splicing devices without covers, since with these yarn splicing devices the yarn insertion slit is usually laid out relatively narrowly.
Yarn splicing devices whose splicing channel can be closed by means of a pivotably seated cover element have the disadvantage that such devices are often relatively bulky, i.e. such yarn splicing devices require a relatively large installation space.
It is accordingly an object of the present invention to create a yarn splicing device that overcomes the aforesaid disadvantages.
This object is addressed by a yarn splicing device comprising a splicing channel that can be charged with compressed air for the pneumatic connection of two yarn ends, wherein the yarn splicing device has two rotatably seated prism elements that are each pivotable between a yarn reception position and a splicing position such that in the splicing position a splicing channel is formed that can be charged with compressed air between the prism elements.
An advantage of the yarn splicing device of the present invention is that it is extremely compact in its construction. Furthermore, the yarn ends to be spliced together can be positioned without problems in the area of the splicing channel. Thus, because of the employment of two rotatably seated prism elements it is possible to simply securely position the yarn ends that have been preplaced by a suction nozzle or a gripper tube inside the splicing channel and to fix them in place there for the splicing process.
In one embodiment of the present invention, at least one of the prism elements has a compressed air injection opening.
Such a compressed air injection opening makes the directed injection of splicing air into the splicing channel formed by the prism element possible, such that the prism element without a compressed air injection opening acts as the cover element.
In another embodiment of the present invention, an air distribution channel is cut into a respective prism element. Preferably, two compressed air injection openings branch from the air distribution channel and terminate in the splicing channel. Splicing air can be blown into the splicing channel via the air distribution channel and the compressed air injection openings. This splicing air provides the mutual swirling together of the yarn ends positioned in the splicing channel, whose spinning twist had previously been removed to the greatest extent possible.
Thus, it is possible to produce dependable and lasting yarn connections.
In yet another embodiment of the present invention, the compressed air injection openings each terminate tangentially in the splicing channel.
The tangential arrangement of the injection openings assures that an at least partially rotating air flow is created inside the splicing channel.
Such a rotating air flow results in solid, almost finished yarn-like yarn connections.
In still yet another embodiment of the present invention, the two prism elements are identical and each has a compressed air injection opening.
By using identical components it is possible to make the production costs of these parts relatively advantageous, yet if these parts are produced as injection-molded or die-cast parts, storage is also simplified.
In another embodiment of the present invention, the prism elements each comprise an approximately cylindrical prism body and a releasable rear cover element.
Thus, the prism bodies are designed such that in the yarn pickup position there is sufficient space provided between the prism bodies for inserting the yarn that is to be spliced together.
In the splicing position, the prism bodies rest against the opposite prism body such that a splicing channel that is closed to the greatest extent is formed between the prism bodies.
In yet another embodiment of the present invention, the rear cover elements that can be fixed in place on the prism elements, each have a convexly rounded sealing surface into which an air connection bore has been cut.
Each of these convexly rounded sealing surfaces of the cover elements matches correspondingly concavely arched sealing surfaces of a stationary connecting means which can be charged with compressed air.
Thus, the connecting means are connected with a compressed air source via a pneumatic line into which an electromagnetic valve, for example, has been inserted so that it is possible by means of an appropriate control of the electromagnetic valve to blow splicing air in a directed manner into the splicing channel. For example, over the length of time the electromagnetic valve is open it is possible to match the effect of the splicing air individually to the respective material or the thickness of the yarn ends to be spliced together.
In still yet another embodiment of the present invention, the prism elements are seated, pivotable to a limited extent, in a base body of the yarn splicing device.
Driving of the prism elements takes place advantageously here by means of a drive mechanism, for example a step motor that can be controlled by means of a work station computer.
Such step motors are commercially available, cost-effective mass-produced components that have been tested in various fields of employment and have proven to be dependable and have a long service life.
Further details of the present invention can be gathered from a non-limiting exemplary embodiment presented in the following description with reference made to the drawings.